Which of the following statements concerning cost formulas in a periodic inventory system is incorrect? a Select one: n O A. The results under FIFO in a periodic system are the same as in a perpetual system. O B. The cost of goods sold would be lower using FIFO than weighted average in a period of rising prices. OC. The results under weighted average in a periodic system are not the same as in a perpetual system OD. When using the weighted average cost formula, a new weighted average cost per unit is calculated after each purchase